LITMIR.BIZ

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which varies in size, is sometimes broken into several spots, or is sometimes wanting altogether. The eyes (fig. 20) are near together, the upper row curved down at the ends. The maxillæ are straight, with the sides nearly parallel, and the labium is shorter than wide. The males are usually smaller than the females and have the red spot larger. These spiders live among stones in dry open places. They are easily alarmed and move very rapidly. The flat, parchment-like cocoons found on stones are probably made by this species.

Fig. 23. Fig. 24. Geotrecha bivittata.—Upper and under views of female enlarged four times.

      Geotrecha bivittata.—The same size as G. crocata but much lighter colored, and with two white stripes across the abdomen (fig. 23). The cephalothorax is a little narrower behind than it is in crocata. Its color varies from orange to dark brown. The femora of all the legs are striped lengthwise with brown and yellow. The hind legs are brown, with a little yellow on the upper side of the patella and tibia. The other legs are yellow, sometimes with brown stripes on the under side. The white marks on the abdomen extend underneath halfway to the middle line. The sternum and under side are light brown. It lives under leaves at all seasons.

Figs. 25, 26, 27, 28. Micaria longipes.—28, Male enlarged four times. 25, eyes seen from in front. 26, maxillæ, labium, and ends of mandibles from below. 27, Southern variety, Micaria aurata. Colored orange, with black and white markings.

Micaria longipes or aurata.—A quarter of an inch long or less, and resembling an ant both in size and color (fig. 28). The cephalothorax is twice as long as wide, and only a little widened in the middle. It is highest in the middle, curving downward at both ends. The front row of eyes (fig. 25) is nearly straight and the upper row curved, with the middle eyes highest and the eyes all farther apart than in the lower row. The abdomen is one-half longer than the cephalothorax and about as wide, blunt at both ends and drawn in a little at the sides and above at a point a third of its length from the front. The legs are long and slender, the fourth pair longest. The colors are light yellow brown, with gray hairs and scales which on the abdomen have green and red metallic reflections. The legs are darker from before backward, the front pair all light yellow except the femur, and the third and fourth pairs with longitudinal brown stripes that nearly cover the tarsal joints. The abdomen has a pair of transverse white stripes near the constricted part and another pair less distinct at the front end. The under side is as dark as the upper. The white markings extend underneath halfway to the middle line. The maxillæ are nearly straight on the outer edge and a little widened toward each other at the ends. The labium is narrowed at the end and a little longer than wide (fig. 26).

      There is an orange-colored Micaria from Long Island, N.Y., and farther south (probably what is described by Hentz under the name Herpyllus auratus), that seems to belong to this species (fig. 27). Its size and markings are the same, and the epigynum is like that of longipes. The cephalothorax, abdomen, and femora of all the legs are bright orange color, with brilliant yellow and green reflections. The spinnerets are black, and there are five or six transverse black marks on the hinder half of the abdomen and some irregular black spots around the white bands.

Figs. 29, 30, 31, 32. Phrurolithus alarius.—31, female in a natural position, with legs drawn up over the back, enlarged eight times. 29, one of the front legs to show spines. 30, eyes from in front. 32, maxillæ, labium, and ends of mandibles.

      Phrurolithus alarius.—A small and very active spider marked with gray and white and having on the abdomen iridescent green scales (fig. 31). The cephalothorax is nearly as wide behind as it is long. The head is about half as wide as the thorax. The eyes (fig. 30) are large for so small a spider, and cover more than half the width of the head. The middle eyes of the upper row are oval and turned obliquely, diverging toward the front. The labium is short and the maxillæ straight, as in Agrœca and Anyphæna, but wider at the base (fig. 32). The legs are long and slender, except the tibia and metatarsus of the first and second pairs, which are twice as thick as the same joints of the other legs and have on the under side two rows of strong spines (fig. 29). The cephalothorax is light yellowish, with a black line on the edge each side, and two light gray stripes. The abdomen is gray, with transverse white markings that vary greatly in size and shape in different individuals. The abdomen is covered with scales that change from grayish green to pink with the motions of the spider. The legs are pale, except the patella and tibia of the first pair, which are black or dark gray, with the tip of the tibia white. The tibia and patella of the second pair are marked with lighter gray in the same way. It lives among stones in open ground, and runs short distances with great swiftness. When still it lies close to a stone, with the tibiæ drawn up over the back.

      

Figs. 33, 34, 35, 36. Agrœca pratensis.—33, eyes from in front. 34, maxillæ, labium, and ends of mandibles. 35, back of female enlarged four times. 36, under side of female as far back as the epigynum.

      Agrœca pratensis.—A little light-colored spider, resembling the next species, Anyphæna incerta. It is about a fifth of an inch long. The cephalothorax is wide behind and low in front and highest near the dorsal groove. The head is contracted in front of the legs more than it is in incerta. The front row of eyes is nearly straight, the middle pair only a little the higher (fig. 33). The upper row is longer and more curved, with all the eyes about the same distance apart, the middle pair not so much separated as in incerta. The abdomen is widest behind, but not as wide as in incerta. The spinnerets are two-jointed, as in Anyphæna. The legs are long, the fourth pair longest, and are a little thicker than those of incerta. The coxæ of the hind legs almost touch, and the sternum is short and nearly round (fig. 36). The labium is short and the maxillæ straight, as in Anyphæna. The cephalothorax, legs, and mouth parts are light brownish yellow. The cephalothorax has a fine dark line on each side and two broken longitudinal stripes made up of gray marks radiating from the dorsal groove. The abdomen has two rows of gray oblique markings on a light ground. The general appearance is like a small Lycosa. It lives among leaves and short grass. There is little difference between male and female.

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